"If cell phones are no threat to the computer/electrical systems of the plane"
That's just it....IF..
There's STILL alot of concerns about this, its simply not proven to be inconsequential RF interference, and until it is, they can't approve it.
No, not really. Modern cell phones do not interfere. This myth was born from old analog "cell" phones which had a chance of interfering with some older equipment. Now this myth is perpetuated by the airlines for a variety of social and political reasons. Have you watched Myth Busters? »kwc.org/mythbusters/2006/04/epis···ane.html